Definition & Meaning of "butt knuckler"in English

What is the origin of the term "butt knuckler" and how is it used?

"Butt knuckler" is a slang insult that emerged in late 20th–21st-century English, formed by combining "butt" (the rear) with "knuckler" (suggesting clumsiness or roughness) to label someone as foolish, obnoxious, incompetent, or contemptible. The term plays on crude physical imagery to convey ridicule and mockery. It is primarily used in informal conversation, online banter, and comedic contexts to exaggerate someone's incompetence or silliness. The term is derogatory but relatively mild, often humorous rather than deeply offensive, and is rarely used in serious or formal discourse.